SECTION VII. 



NITROGEN BASES. 



Ammonia is said to have basic properties because it can form 

 salts by combining with acids. This salt formation, which 

 may be illustrated by the conversion of ammonia into am- 

 monium chloride, is due to the unsaturated nature of the 

 trivalent nitrogen atom, and its tendency to assume the penta- 

 valent condition. 



>J' 



'"'— H 

 Ammonia 



N' 



H 

 H 

 H 

 H 

 CI 



Ammonium chloride 



The replacement of one or more of the hydrogen atoms in 

 ammonia by organic radicles, such as methyl, CH3 — , ethyl, 

 C2H5 — , or phenyl, CgHj — , gives rise to compounds known as 

 amines or substituted ammonias, which still retain the property 

 of salt formation possessed by the parent substance ammonia. 



For example : — 



H 

 CH3N"'<^ + HCl 



H 

 Methylamine 



(C,H,), = NH + HI 

 Diethylamine 



(CH3)3 = N + HBr 



CH3— N' 



Methylamine hydrochloride, or 

 Methylammonium chloride 



-> (C,H,), = N-H 



\l 

 Diethylamine hydriodide 



-> (CH3)3 = N<r 



^Br 



Trimethylamine 



Trimethylamine hydrobromide 



358 



